Process flow of spray polyurea anti-corrosion for water tank

Construction process flow

Scaffolding - Welding point polishing - Sand blasting and rust removal - Primer application twice - Polyurea spraying - Acceptance

When setting up scaffolding, at least one arm long distance should be left for the convenience of spraying operations.

1. Grinding, sandblasting, and primer construction of seams and welding points

To obtain a smooth transition coating without pinhole leakage points, it is recommended to manually polish all welds and solder joints with an angle grinder until a smooth transition is achieved.

After sandblasting, to prevent rusting, if polyurea spraying cannot be carried out within 8 hours, use a short bristle roller to apply the primer once at a coating rate of 0.15 kilograms per square meter. It is necessary to confirm in advance that the short hair drum is resistant to solvent corrosion, and non corrosion-resistant drums cannot be used, otherwise there may be construction defects such as foaming and shedding.

The sandblasting material should be steel sand with sharp corners or 3 # copper ore sand, with an expected roughness of 50 microns.

2. Primer construction

Prepare the corresponding amount of primer according to the required coating area and recommended coating rate. Use a confirmed safe pneumatic mixer to mix the primer and let it sit for 20 minutes before proceeding with painting. When the temperature is high, the curing time can be appropriately reduced.

Before the construction of polyurea, the surface of the primer should be cleaned thoroughly. If the primer cannot be sprayed within 48 hours after being brushed, the dust on the surface after sandblasting should be cleaned, and a short hair roller should be used to apply the primer again at a rate of 0.15 kilograms per square meter.

The primer surface can be sprayed with polyurea within 48 hours of drying.

If the polyurea cannot be sprayed after 48 hours, it is necessary to reapply the primer. and so on.

3. Polyurea spraying

Dry the primer and spray polyurea within 48 hours.

When there is overlap between polyurea and polyurea overnight or more than 2 hours, the overlap surface should be coated with primer.

The coating interval between polyurea and polyurea is 2 hours.

Cleaning of spray materials: Due to the use of inner wall spraying, a crucial measure during polyurea spraying is to use tools such as electric angle grinders or blades to clean the spray materials before spraying. This is a key step in achieving an ideal appearance

Polyurea repair: Leakage points and areas with insufficient thickness found during electric spark testing need to be repaired before acceptance. During repair, the surface of the old polyurea needs to be polished and coated with primer once, followed by spraying polyurea for repair.